Krauss on Science

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World-famous ASU Physicist Lawrence Krauss makes his monthly visit to the Arizona Horizon set to talk about science. He’ll discuss “baby pictures” of the Big Bang and new earth-like planets recently discovered.

Ted Simons: Arizona State University physicist Lawrence Krauss stops by the "Arizona Horizon" set once a month to talk about the latest in science news. In a recent conversation I spoke with Krauss about baby pictures from the big bang.

Lawrence Krauss: It's great to be back, as always.

Ted Simons: We've got a bunch of things to talk about. A couple of huge things to talk about including baby picture from the big bang, these are kind of baby pictures.

Lawrence Krauss: They are baby pictures! Unlike normal baby pictures, where I think only the parents like to look at them. In this case, they're pictures everyone should be interested in. They're pictures that go back and show us what the universe looked like when it was only about 380,000 years after the big bang. 13.8 billion years ago. I say that now, because in fact from these new baby pictures we have been able to learn new things about the University that have changed some of the numbers slightly.

Ted Simons: So what we're looking at right now, this is kind of a radiation view of the universe?

Lawrence Krauss: What you're looking at is first of all projection of the -You see projections of the earth, the surface of the earth and project them on a flat plane. Imagine taking projection of the sky and all direction and projecting it on a flat plane. There would be a horizontal line, through that ellipse and that would be where our galaxy sits. Our spiral milky way galaxy would be right in the horizontal line in the equator of that image. Then the upper part of the image is the northern hemisphere and the bottom part is the southern hemisphere. What we're seeing here, of course they're not real images, but false coloring. They're real images, but false color images of hot spots and cold spots in this radiation called the cosmic microwave background radiation. The afterglow of the big bang.

Ted Simons: When you say radiation, you know this is radiation because the radiation started when everything cooled down?

Lawrence Krauss: The universe was very hot in early times, and it was so hot, in fact, that matter didn't exist in a neutral form. Hydrogen which is protons and electrons, every time a proton tried to capture an electron the radiation was so hot it would break it apart. That meant that matter existed in a plasma. A plasma is opaque radiation. When the universe became 380,000 years old the radiation cooled below 3,000 degrees, a little warmer than Phoenix in July, and then the matter became neutral and it became transparent to radiation. So that radiation is streaming at us from all directions from that time when the universe first became the matter in the universe first -- In the universe first became neutral. It's streaming at us from all different directions and the radiation has cooled down, it was 3,000 degrees, it's now three degrees because the universe has expanded by a factor of a thousand since then. And it's in the microwave background. If you're as old as you or I, you've seen it. Because remember the days before cable TV? Back when the TV programs went off the air and you saw static?

Ted Simons: First you saw the national anthem, and then…

Lawrence Krauss: Then the test pattern, and then static. If you're as desperate to watch TV as I was, I waited until the static came. Then 1% of the radiation of the static you saw on the TV is radiation from the big bang.

Ted Simons: So you're literally being bombarded by something that's 13 billion years old?

Lawrence Krauss: Exactly. What's amazing, this radiation has been coming at us forever and it wasn't discovered until 1965 in New Jersey of all places. By two people who didn't know what they were looking for. They were at bell labs building a radio telescope, and that meant they had a radio receiver and they put it toward the sky and they kept getting noise. They got rid of what they called a white dialectric material inside, which is pigeon droppings, and they didn't know what the problem was. They went down the road to some astronomers at Princeton, who were sad to hear the news because they were building an antenna to look for the noise, and those two guys who discovered that noise, which was the radiation from the big bang, won the Nobel prize for discovering proof. It's one of the first definitive bits of proof the big bang really happened. By the way, the big bang really happened. It's not controversial, there's no need to worry about teaching it. It really happened. And when we look at this radiation, which gives us a picture of the universe, we can tell all sorts of new things about the universe. This new picture from the plank satellite, the satellite that was launched by the European space agency, it's been going around for the last few years, measuring the entire sky, and getting a picture which is probably 10 times more accurate than any picture, baby picture we've had up to now. And it's allowed us to know, for example, when I came on the show a year ago would I have said the age of the universe was 13.7 billion years approximately. Now we know it's closer to 13.8 billion years. And we've known the amount of dark matter, dark energy is different. On the whole it confirms everything we knew. But there's some mystery still.

Ted Simons: And I was reading about, there are hot spots and cold spots, first can you see them in the image? Can you tell where they are?

Lawrence Krauss: The hot spots and cold spots -- The blue spots I think are colored to be the colder regions and the other spots are colored to be the hotter regions. Those are small temperature -- What's really wonderful about that, those where the lumps are-- We think we're created at the big bang itself. Which would later collapse and cause everything -- Those would collapse to formality galaxies, stars, planets, aliens and TV broadcasts.

Ted Simons: So you do kind of get to see what happened prior to that 300 some-odd thousands.

Lawrence Krauss: We think they were imprinted at the beginning of time. That allows to us test our theories about what the universe was like not when it was 380,000 years old, but a billionth of a billionth of a second old.

Ted Simons: And so basically what you're looking at became galaxies, stars, planets.

Lawrence Krauss: Exactly. And the question is, how did it get there? What was the physics of the beginning of time? That's what people like me get paid to think about.

Ted Simons: Not all questions are answered by the baby pictures.

Lawrence Krauss: No, no, no. As usual, more questions than answers. In fact, there are some weird things, which could just be statistics but the problem is, we only have one universe. Most of us do. As far as we know. Most of us experience, some people may claim to experience more. I'll make a political joke, but I won't. Because we only have one universe, if these things are statistical, it turns out there's some weird anomalies. There's a few more large hot spots in the northern hemisphere than the southern hemisphere. We wouldn't expect that. Is that an accident of statistics? Or is that significant? Does that point to new physics? Was a -- With a sample of one it's hard to say. We may have to learn more, but there are open questions and that's what makes science exciting.

Ted Simons: Oh that's fantastic, and something else that's exciting -- By the way, it looks like this big old thing, but when you realize what it is. it's remarkable.

Lawrence Krauss: Exactly. It is. And we're very proud. Any baby picture demonstrated and we're very proud.

Ted Simons: Yes. A couple of earthlike planets found -- Like a 1,200 some-odd light years away?

Lawrence Krauss: Yes, 1,200 light years away. Probably one of the most exciting discoveries of the Kepler satellite, which is a satellite, we've talked about some of the other planets that come from them, here on the screen you can see for the first time not only has it been able to discover planets that are comparable in size to the earth, they're actually located around a star slightly smaller than our sun, but at a distance that is not too -- In comparison is not that different from the earth. They're going around, one is 150 days every -- Its year is 150 days, the other is 260 days, and they're in the region, the right size, and they're in the region where we think liquid water could exist. So they're in my mind the very first sort of candidates for actual habitable planets elsewhere there. May be life there.

Ted Simons: You're saying that 1,200 light years away there's a sun that's not as strong as ours, there are five or six planets?

Lawrence Krauss: Six planets. A solar system not that different than ours.

Ted Simons: And two of them, the 62E and the 62F are very similar to Earth.

Lawrence Krauss: They're a little bigger, 50% to 60% bigger than Earth, but if you had to pick a place outside of our solar system where you might be reasonably certain that life could form, those would be the places. But that's just the tip of the iceberg. There are a hundred billion stars in our galaxy. We're learning pretty well every star has planets around it. I would suspect that there are at least a billion habitable planets in our galaxy.

Ted Simons: And I hear about habitable zone and the Goldilocks zone. What is that?

Lawrence Krauss: The point is, we are -- If you look at our own solar system, things are just right here. Mars is a little too small and far away, Venus, used to have -- Used to not be hot, but had a runaway greenhouse effect. It's too hot now. We're right in the region where right now liquid water can exist in a rocky planet and by the way, it's not just right for long. This program can't go on forever. In 2 billion years, the earth is going to heat up and be much like Venus right now. No matter what we do. I know you'll talk about sustainability next. No matter what we do, the sun is going to be 15% brighter in 2 billion years and then we'll no longer be in the Goldilocks zone. And if life wants to continue on earth we have a few choices. Maybe move to Mars, or maybe move the earth. We could do that maybe.

Ted Simons: Or maybe take a ride up to Kepler 62E.

Lawrence Krauss: After maybe two or three million year voyage could you do that.

Ted Simons: Let me ask you about that. 1,200 light years, right now, inconceivable. Is it possible, is it possible to ever travel at the speed of light or beyond?

Lawrence Krauss: We didn't say it's impossible, warp drive we can have a discussion next time about warp drive. It doesn't violate the laws of physics, but it is prohibited -- It is an academic question. To travel at near the speed of light would cost the -- Would take so many resources, you'd have to harness the power output of a star to get a spaceship and just have the fuel. The fuel -- If you wanted to take an existing spacecraft with existing rocket fuel and accelerate to it half the speed of light the amount of fuel required would be more than the mass of the entire visible universe. So NASA made appropriate funds for it but it's just not going to happen.

Ted Simons: What a wet blanket you are.

Lawrence Krauss: We aren't going to be traveling at near the speed of light. It's an economically prohibitive thing. But the good news, that means aliens aren't coming here!

Ted Simons: I was just going to say, doesn't that make the idea of spaceships visiting us a little unlikely?

Lawrence Krauss: Not only a little unlikely, incredibly unlikely. It just hasn't happened. Unfortunately people -- We'd like to think-- None of us want to be alone. We want to know if we're alone in the universe. Of course there might be microbial life on the planets, but what we care about, is there intelligent life elsewhere in the universe.

Ted Simons: Do you think there's water on these things?

Lawrence Krauss: I would bet there's a reasonable likelihood of water. Because there's lots of water produced around stars. When we look at elsewhere in our solar system and the universe, all the ingredients of life are there. Water, organic materials, and sunlight. We've not only discovered rather complex bases of amino acids on comets, some recent experiments in Berkeley just showed that even more complex molecules can be create bide chemistry on those comets. If you expose them to ultra violet light you can create what are called di-peptides -- Really, the basis of the complex molecules that form RNA and DNA. So not only would I not be surprised if there's water, I wouldn't be surprised if there's microbes. I would be surprised if there's intelligent life, but --

Ted Simons: What about sea creatures? If you got water wouldn't have you a sea creature?

Lawrence Krauss: Well first you have to make the microbes that makes sea creatures. It took a long time for that to happen here on Earth. It could -- The point is, that's what's exciting. We don't know what's possible. There's a whole universe of things to find out. That's why it's fun to come on each week --

Ted Simons: Is the Kepler mission -- What is it going to do?

Lawrence Krauss: It looks at planets, the stars. It looks for how the stars get dimmer when the planets go in front of them. A little tiny planet goes in front of a star and you see the star change in brightness by 1%, but you see it happen on a regular basis. And then you can follow it up and see if the star is wiggling back and forth in response to the gravitational pull of the planet. They've discovered, confirmed several hundred stars, but they've discovered over 2,000, -- Not stars, planets. They've discovered over 2,000 planet candidates, and what we're finding is that basically every star probably has a solar system around it. It's really neat.

Ted Simons: Last point, the constellation Lira --

Lawrence Krauss: I don't worry about constellations.

Ted Simons: I love that stuff and I know VEGA is the bright star you can see. If I look at VEGA I could be looking up somewhere within that constellation

Lawrence Krauss: Somewhere in that region, you could be -- There could be stars and sea creatures and there could be -- In 1,200 years, they'll be able to listen to this program.

Ted Simons: Well, lucky them. Good to have you here. Thanks for joining us.

Lawrence Krauss:Physicist, ASU;

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